1. Field of the Invention
The present invention concerns electric cigar lighters, or multifunction electric sockets, in particular intended to equip motor vehicles. It relates more particularly to means for illuminating the cigar lighters or multifunction sockets, being in particular in the form of illuminating rings associated with an illuminating module.
2. Description of the Related Art
As is known, cigar lighters are illuminated by a lamp mounted in an illuminating module. The electrical supply to this lamp is made by means of blades of conductive material. These blades are on the one hand in electrical contact with the body of the cigar lighter forming an earth. They are on the other hand either in contact with a tongue of the connector or directly connected to the electrical supply cable. An example of an illuminating module carried by an illuminating ring of a cigar lighter is described in the patent FR 2 758 111, which is equivalent to U.S. Pat. No. 5,928,539.
It is sought to improve the reliability and longevity of lamps. This is the reason why it was proposed in the patent application EP 0 819 575 to replace the conventional lamp with a light emitting diode, generally designated by the English abbreviation “LED”. Diodes have in fact generally a longer service life than conventional lamps, and a lower electrical consumption. However, the arrangement of the diode in the cigar lighter according to this document does not entirely give satisfaction: it does not make it possible to illuminate the ashtray, and leaks of light are to be feared through reflection on the metal body of the cigar lighter. Also it does not appear to afford a great deal of flexibility in its electrical supply method. Its mounting is not very compact. It also makes it necessary to use a manual soldering method for the wires connecting to the friction contacts and to place the diode, as well as the resistor and the friction contacts, on a slide before soldering them together to produce the electrical circuit.
A first improvement to LED illumination modules was proposed in the patent EP 1 516 777: it is a case of an illuminating ring on which an illuminating module is mounted, the illuminating module comprising a printed circuit provided with at least one light emitting diode, a cover intended to at least partly house the printed circuit, and at least two electrical supply tongues for the said printed circuit, mechanically fixed to the cover.
However, it is still possible to further improve the design of these illuminating modules, in particular on an optical level, so that the light flux emitted by the light emitting diode is better used, and on an electrical and mechanical level so that it is simpler to assemble the illuminating module and to make its electrical connections.